console.log(2 * 3)

let i = 5

//number
console.log(typeof i)

class user {

}

let u = new user();
console.log(typeof (u))


// location.href = 'http://www.baidu.com'

i = 'ok'
//string
console.log(typeof (i))

for (let i = 1; i <= 5; i++) {
    console.error(i)
}
